1. Field of the Invention
The invention is related to the field of well flow measurements, and in particular, to oil flow computers.
2. Description of the Prior Art
Gas and oil wells may have multi-phase flow exiting from the well head. The total flow from the well head needs to be measured. To measure the total flow, the gas flow is typically separated from the liquid flow and the gas and liquid flows are measured separately. The gas and liquid flows may be measured by two different Coriolis flow meters. The liquid flow typically contains both oil and water. To accurately measure the amount of oil in the liquid flow, the amount of water in the liquid flow must be determined. To determine the amount of water in the flow, the density of the water needs to be determined. Currently the density of water is determined by periodically taking a sample of the water flowing from the well head and determining the density using a hydrometer. This method has a number of problems. One problem is that the density of the water can change over time. If the density of the water changes and the old density measurement is used, the calculation for the amount of oil in the flow becomes inaccurate. The inaccuracy is more of a problem in high water cut flows than in low water cut flows. One way to minimize the inaccuracies is to frequently sample the water density. However, removing the sample from the system and testing the density may be a labor and time consuming task.
Therefore there is a need for a better system and method for determining the amount of oil in the flow.